source3/nmbd/nmbd_synclists.c

   1 /*
   2    Unix SMB/CIFS implementation.
   3    NBT netbios routines and daemon - version 2
   4    Copyright (C) Andrew Tridgell 1994-1998
   5    Copyright (C) Luke Kenneth Casson Leighton 1994-1998
   6    Copyright (C) Jeremy Allison 1994-1998
   7
   8    This program is free software; you can redistribute it and/or modify
   9    it under the terms of the GNU General Public License as published by
  10    the Free Software Foundation; either version 3 of the License, or
  11    (at your option) any later version.
  12
  13    This program is distributed in the hope that it will be useful,
  14    but WITHOUT ANY WARRANTY; without even the implied warranty of
  15    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  16    GNU General Public License for more details.
  17
  18    You should have received a copy of the GNU General Public License
  19    along with this program.  If not, see <http://www.gnu.org/licenses/>.
  20 */
  21
  22 /* this file handles asynchronous browse synchronisation requests. The
  23    requests are done by forking and putting the result in a file in the
  24    locks directory. We do it this way because we don't want nmbd to be
  25    blocked waiting for some server to respond on a TCP connection. This
  26    also allows us to have more than 1 sync going at once (tridge) */
  27
  28 #include "includes.h"
  29 #include "system/filesys.h"
  30 #include "../librpc/gen_ndr/svcctl.h"
  31 #include "nmbd/nmbd.h"
  32 #include "libsmb/libsmb.h"
  33 #include "libsmb/clirap.h"
  34 #include "../libcli/smb/smbXcli_base.h"
  35 #include "lib/util/string_wrappers.h"
  36 #include "source3/lib/substitute.h"
  37
  38 struct sync_record {
  39         struct sync_record *next, *prev;
  40         unstring workgroup;
  41         unstring server;
  42         char *fname;
  43         struct in_addr ip;
  44         pid_t pid;
  45 };
  46
  47 /* a linked list of current sync connections */
  48 static struct sync_record *syncs;
  49
  50 static FILE *fp;
  51
  52 /*******************************************************************
  53   This is the NetServerEnum callback.
  54   Note sname and comment are in UNIX codepage format.
  55   ******************************************************************/
  56
  57 static void callback(const char *sname, uint32_t stype,
  58                      const char *comment, void *state)
  59 {
  60         fprintf(fp,"\"%s\" %08X \"%s\"\n", sname, stype, comment);
  61 }
  62
  63 /*******************************************************************
  64   Synchronise browse lists with another browse server.
  65   Log in on the remote server's SMB port to their IPC$ service,
  66   do a NetServerEnum and record the results in fname
  67 ******************************************************************/
  68
  69 static void sync_child(char *name, int nm_type,
  70                        char *workgroup,
  71                        struct in_addr ip, bool local, bool servers,
  72                        char *fname)
  73 {
  74         fstring unix_workgroup;
  75         struct cli_state *cli;
  76         uint32_t local_type = local ? SV_TYPE_LOCAL_LIST_ONLY : 0;
  77         struct sockaddr_storage ss;
  78         NTSTATUS status;
  79
  80         /* W2K DMB's return empty browse lists on port 445. Use 139.
  81          * Patch from Andy Levine andyl@epicrealm.com.
  82          */
  83
  84         in_addr_to_sockaddr_storage(&ss, ip);
  85
  86         status = cli_connect_nb(name, &ss, NBT_SMB_PORT, nm_type,
  87                                 get_local_machine_name(), SMB_SIGNING_DEFAULT,
  88                                 0, &cli);
  89         if (!NT_STATUS_IS_OK(status)) {
  90                 return;
  91         }
  92
  93         status = smbXcli_negprot(cli->conn, cli->timeout, PROTOCOL_CORE,
  94                                  PROTOCOL_NT1);
  95         if (!NT_STATUS_IS_OK(status)) {
  96                 cli_shutdown(cli);
  97                 return;
  98         }
  99
 100         status = cli_session_setup_anon(cli);
 101         if (!NT_STATUS_IS_OK(status)) {
 102                 cli_shutdown(cli);
 103                 return;
 104         }
 105
 106         if (!NT_STATUS_IS_OK(cli_tree_connect(cli, "IPC$", "IPC", NULL))) {
 107                 cli_shutdown(cli);
 108                 return;
 109         }
 110
 111         /* All the cli_XX functions take UNIX character set. */
 112         fstrcpy(unix_workgroup, cli->server_domain ? cli->server_domain : workgroup);
 113
 114         /* Fetch a workgroup list. */
 115         cli_NetServerEnum(cli, unix_workgroup,
 116                           local_type|SV_TYPE_DOMAIN_ENUM,
 117                           callback, NULL);
 118
 119         /* Now fetch a server list. */
 120         if (servers) {
 121                 fstrcpy(unix_workgroup, workgroup);
 122                 cli_NetServerEnum(cli, unix_workgroup,
 123                                   local?SV_TYPE_LOCAL_LIST_ONLY:SV_TYPE_ALL,
 124                                   callback, NULL);
 125         }
 126
 127         cli_shutdown(cli);
 128 }
 129
 130 /*******************************************************************
 131   initialise a browse sync with another browse server.  Log in on the
 132   remote server's SMB port to their IPC$ service, do a NetServerEnum
 133   and record the results
 134 ******************************************************************/
 135
 136 void sync_browse_lists(struct work_record *work,
 137                        char *name, int nm_type,
 138                        struct in_addr ip, bool local, bool servers)
 139 {
 140         struct sync_record *s;
 141         static int counter;
 142         int fd;
 143
 144         /* Check we're not trying to sync with ourselves. This can
 145            happen if we are a domain *and* a local master browser. */
 146         if (ismyip_v4(ip)) {
 147 done:
 148                 return;
 149         }
 150
 151         s = SMB_MALLOC_P(struct sync_record);
 152         if (!s) goto done;
 153
 154         ZERO_STRUCTP(s);
 155
 156         unstrcpy(s->workgroup, work->work_group);
 157         unstrcpy(s->server, name);
 158         s->ip = ip;
 159
 160         if (asprintf(&s->fname, "%s/sync.%d", lp_lock_directory(), counter++) < 0) {
 161                 SAFE_FREE(s);
 162                 goto done;
 163         }
 164         /* Safe to use as 0 means no size change. */
 165         all_string_sub(s->fname,"//", "/", 0);
 166
 167         DLIST_ADD(syncs, s);
 168
 169         /* the parent forks and returns, leaving the child to do the
 170            actual sync */
 171         CatchChild();
 172         if ((s->pid = fork())) return;
 173
 174         BlockSignals( False, SIGTERM );
 175
 176         DEBUG(2,("Initiating browse sync for %s to %s(%s)\n",
 177                  work->work_group, name, inet_ntoa(ip)));
 178
 179         fd = open(s->fname, O_WRONLY|O_CREAT|O_TRUNC, 0644);
 180         if (fd == -1) {
 181                 _exit(1);
 182         }
 183
 184         fp = fdopen(fd, "w");
 185         if (!fp) {
 186                 _exit(1);
 187         }
 188         fd = -1;
 189
 190         sync_child(name, nm_type, work->work_group, ip, local, servers,
 191                    s->fname);
 192
 193         fclose(fp);
 194         _exit(0);
 195 }
 196
 197 /**********************************************************************
 198  Handle one line from a completed sync file.
 199  **********************************************************************/
 200
 201 static void complete_one(struct sync_record *s,
 202                          char *sname, uint32_t stype, char *comment)
 203 {
 204         struct work_record *work;
 205         struct server_record *servrec;
 206
 207         stype &= ~SV_TYPE_LOCAL_LIST_ONLY;
 208
 209         if (stype & SV_TYPE_DOMAIN_ENUM) {
 210                 /* See if we can find the workgroup on this subnet. */
 211                 if((work=find_workgroup_on_subnet(unicast_subnet, sname))) {
 212                         /* We already know about this workgroup -
 213                            update the ttl. */
 214                         update_workgroup_ttl(work,lp_max_ttl());
 215                 } else {
 216                         /* Create the workgroup on the subnet. */
 217                         work = create_workgroup_on_subnet(unicast_subnet,
 218                                                           sname, lp_max_ttl());
 219                         if (work) {
 220                                 /* remember who the master is */
 221                                 unstrcpy(work->local_master_browser_name, comment);
 222                         }
 223                 }
 224                 return;
 225         }
 226
 227         work = find_workgroup_on_subnet(unicast_subnet, s->workgroup);
 228         if (!work) {
 229                 DEBUG(3,("workgroup %s doesn't exist on unicast subnet?\n",
 230                          s->workgroup));
 231                 return;
 232         }
 233
 234         if ((servrec = find_server_in_workgroup( work, sname))) {
 235                 /* Check that this is not a locally known
 236                    server - if so ignore the entry. */
 237                 if(!(servrec->serv.type & SV_TYPE_LOCAL_LIST_ONLY)) {
 238                         /* We already know about this server - update
 239                            the ttl. */
 240                         update_server_ttl(servrec, lp_max_ttl());
 241                         /* Update the type. */
 242                         servrec->serv.type = stype;
 243                 }
 244                 return;
 245         }
 246
 247         /* Create the server in the workgroup. */
 248         create_server_on_workgroup(work, sname,stype, lp_max_ttl(), comment);
 249 }
 250
 251 /**********************************************************************
 252  Read the completed sync info.
 253 **********************************************************************/
 254
 255 static void complete_sync(struct sync_record *s)
 256 {
 257         FILE *f;
 258         char *server;
 259         char *type_str;
 260         unsigned type;
 261         char *comment;
 262         char line[1024];
 263         const char *ptr;
 264         int count=0;
 265
 266         f = fopen(s->fname, "r");
 267
 268         if (!f)
 269                 return;
 270
 271         while (!feof(f)) {
 272                 TALLOC_CTX *frame = NULL;
 273
 274                 if (!fgets_slash(NULL, line, sizeof(line), f))
 275                         continue;
 276
 277                 ptr = line;
 278
 279                 frame = talloc_stackframe();
 280                 if (!next_token_talloc(frame,&ptr,&server,NULL) ||
 281                     !next_token_talloc(frame,&ptr,&type_str,NULL) ||
 282                     !next_token_talloc(frame,&ptr,&comment,NULL)) {
 283                         TALLOC_FREE(frame);
 284                         continue;
 285                 }
 286
 287                 sscanf(type_str, "%X", &type);
 288
 289                 complete_one(s, server, type, comment);
 290
 291                 count++;
 292                 TALLOC_FREE(frame);
 293         }
 294         fclose(f);
 295
 296         unlink(s->fname);
 297
 298         DEBUG(2,("sync with %s(%s) for workgroup %s completed (%d records)\n",
 299                  s->server, inet_ntoa(s->ip), s->workgroup, count));
 300 }
 301
 302 /**********************************************************************
 303  Check for completion of any of the child processes.
 304 **********************************************************************/
 305
 306 void sync_check_completion(void)
 307 {
 308         struct sync_record *s, *next;
 309
 310         for (s=syncs;s;s=next) {
 311                 next = s->next;
 312                 if (!process_exists_by_pid(s->pid)) {
 313                         /* it has completed - grab the info */
 314                         complete_sync(s);
 315                         DLIST_REMOVE(syncs, s);
 316                         SAFE_FREE(s->fname);
 317                         SAFE_FREE(s);
 318                 }
 319         }
 320 }